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03:45 IWF (Göttingen) German 1982

Diffusion in Abhängigkeit vom Molekulargewicht am Beispiel verschiedener Farbstoffe

The dyes chrysoidin (mol. wt. 249), orange G (452), acid fuchsin (586), light green (793) diffuse through 10% gelatine columns. The diffusion velocity decreases with increasing molecular weight and continuous experimental duration (8 days at room temperature).
  • Published: 1982
  • Publisher: IWF (Göttingen)
  • Language: German
08:37 IWF (Göttingen) English 1983

The Zhabotinsky Reaction as a Model of Pattern Formation

Dissipative patterns form in originally simple chemical compounds. Starting from pacesetting centers, chemicalwaves of a redox reaction are transmitted. This can be seen in the change in color of a redox catalyst. The decarboxylation of malonic acid drives the total reaction. Pattern formation in the aggregation of Dictyostelium proceeds analagously (film/photos in cooperation with G. Gerisch, 1963).
  • Published: 1983
  • Publisher: IWF (Göttingen)
  • Language: English
03:58 IWF (Göttingen) English 1983

The Briggs-Rauscher Reaction as a Model of a Chemical Clock

Chemical oscillation reactions are made visible by the periodic appearance and disappearance of an iodine-starch complex. The oscillation is based on autocatalytic reactions, in which intermediary compounds are oxidized and reduced in rhythmic sequence. The total reaction is driven by the decarboxylation of malonic acid. With time-lapse.
  • Published: 1983
  • Publisher: IWF (Göttingen)
  • Language: English
21:39 IWF (Göttingen) German 1983

Brutbiologie von Kupferstecher und Buchdrucker

The reproduction of Ips typographus L. and Pityogenes chalcographus L. in the pine forest is shown in detail partially in time lapse including the boring action of the male, the preparation of the mating place, mating, creation of the female's passage and egg niches, egg laying, transportation of boring dust, larval development, pupa stage and leaving the bark. Places attacked by the insect and damage in the open are shown as well as the significance of the beetle in natural pine woods and commercial forests. The influence of predators on Thanasimus formicans L. is shown.
  • Published: 1983
  • Publisher: IWF (Göttingen)
  • Language: German
16:06 IWF (Göttingen) English 2000

Ecology of the Hover Fly Episyrphus balteatus

The marmalade hoverfly, one of the most common hoverflies, feeds on nectar and pollen. In contrast, the larvae are carnivorous. Fertilised females search for aphid colonies to lay their eggs. Young larvae passively await the contact stimulation by an aphid, then attach themselves securely to the aphid and suck them dry. Larvae of the 3rd stage actively locate aphid colonies, glue the aphids to the substrate and to one another and then successively suck them dry. Two weeks after pupation the fly emerges. Macrophotography, slow-motion up to 400 times.
  • Published: 2000
  • Publisher: IWF (Göttingen)
  • Language: English
04:51 IWF (Göttingen) German 1982

Der Einfluß des Ionenmilieus auf die Quellung von Agar

Preparation of Hofmeister's lyotropic series of cations (Li, Na, K, Rb, Cs) and anions (Cl, Br, J). Due to the agar's negative charge, its degree of imbibitional swelling decreases with increasing ionic radius of the cations and with increasing ionic radius of the anions.
  • Published: 1982
  • Publisher: IWF (Göttingen)
  • Language: German
04:31 IWF (Göttingen) German 1982

Traubesche Zelle

Formation of a Traube Cell is followed in time-lapse photography starting from a crystal of potassium hexacyanoferrate II in a 4% copper sulphate solution through its development until the destruction of the semipermeable deposit membrane and reversal of the cell.
  • Published: 1982
  • Publisher: IWF (Göttingen)
  • Language: German
08:33 IWF (Göttingen) English 1983

Bud Opening in the Common Beech Fagus sylvatica

Animated film documenting the opening process: the buds opens, as in other deciduous trees and bushes, by intercalulary growth of the medial and apical blades as well as simultaneous elongation of the young stem in the bud interior. The opened leaf layers increase by planar growth. Their nature reveals bud blades to be secondary leaves.
  • Published: 1983
  • Publisher: IWF (Göttingen)
  • Language: English
08:33 IWF (Göttingen) German 1983

Knospenentfaltung bei der Rotbuche Fagus sylvatica

Zeitrafferaufnahmen dokumentieren den Entfaltungsvorgang: die Knospen öffnen sich (wie bei anderen Laubbäumen und Sträuchern) durch interkalares Wachstum der mittleren und apikalen Knospenschuppen sowie durch gleichzeitiges Streckenwachstum des jungen Zweiges im Innern der Knospe. Die gefalteten Blattspreiten vergrößern sich durch Flächenwachstum. Die Knospenschuppen sind ihrer morphologischen Natur nach Nebenblätter.
  • Published: 1983
  • Publisher: IWF (Göttingen)
  • Language: German
Offline Collection IWF (Göttingen) German 1979

Die Entwicklung des Denkens nach Jean Piaget - Konkrete Operationen

The development of thought, beginning at around early school age, is described using original experimental conditions as laid down by the Geneva psychologist Jean Piaget. The film shows how the ability to think operatively - with its essential characteristics of reversibility - makes possible the acquisition of stable classificatory and relational concepts as well as invariability (number, substance, quantity).
  • Published: 1979
  • Publisher: IWF (Göttingen)
  • Language: German
16:25 IWF (Göttingen) English 1995

Crystallization of Evaporites in Saltworks

The saltworks of Secovlje (Portoroz, Slovenia) have been producing salt for 700 years. They can be used as a model for the study of microbiology and geochemistry of evaporite sequences of the geological past. The concentration of seawater and the crystallization of carbonates, gypsum and halite (NaCl) are documented and illustrated by graphics and microscope sequences. See films B 1839 and C 1906.
  • Published: 1995
  • Publisher: IWF (Göttingen)
  • Language: English
16:03 IWF (Göttingen) German 2000

Ökologie der Schwebfliege Episyrphus balteatus

Das Doppelbändchen, eine der häufigsten Schwebfliegen, ernährt sich von Nektar und Pollen. Die Larve dagegen lebt räuberisch. Begattete Weibchen suchen zur Eiablage Blattlauskolonien auf. Junge Larven erwarten passiv den Berührungsreiz einer Blattlaus, heften sich an der Laus fest und saugen sie aus. Larven des 3. Stadiums suchen aktiv Blattlauskolonien auf, verkleben die Läuse auf der Unterlage und untereinander und saugen sie nacheinander aus. 2 Wochen nach der Verpuppung schlüpft die Fliege. Makroaufnahmen, Zeitdehnung bis 400fach.
  • Published: 2000
  • Publisher: IWF (Göttingen)
  • Language: German
Offline Collection IWF (Göttingen) German 1973

Vorlesung über Methodik und Anwendung der ärztlichen Hypnose - II. Fraktionierte Hypnose, gestufte Aktivhypnose

The value, importance and use of hypnosis are explained in the framework of a film lecture. Together with the lecture a number of methods are demonstrated, first heterohypnosis, shown with a patient with anxiety syndrome. After an introductory talk and a few preliminary trials an initial hypnosis is demonstrated, induced by the fixation method. Other induction methods follow, like the fascination method, no longer in use, and the easily applied colour contrast method. Subsequently the course of a fractional hypnosis is shown in a subject with a basically sceptical attitude. Lastly a graduated active hypnosis, developed from autogenic training, is demonstrated as a modern form of hypnotherapy.
  • Published: 1973
  • Publisher: IWF (Göttingen)
  • Language: German
Offline Collection IWF (Göttingen) German 1970

Methoden der Hypnoseeinleitung - Fraktionierte Hypnose, gestufte Aktivhypnose

The second part of the film shows the progress of a fractionated hypnosis in a subject with a biased opinion. At last, a graduated activ-hypnosis, developed from autogenetic training, is shown as a modern form of hypnotic therapy.
  • Published: 1970
  • Publisher: IWF (Göttingen)
  • Language: German
09:55 IWF (Göttingen) English 1998

Ballistospore Discharge in Basidiomycetes

Violent spore discharge in mushrooms and other basidiomycetes uses the same mechanism: Due to certain morphological and physiological properties of the spore wall, two liquid droplets are formed. When these two droplets coalesce, the surface area of the fusion droplet is reduced, which instantly generates energy utilized in spore discharge. Investigations were made with Itersonilia perplexans, a ubiquitous fungus which is easily grown in culture. The film introduces the organism, shows for the first time the process preceding spore discharge, and presents experiments which clarify the origin of the drops. The processes and physical forces during spore discharge are explained by animation. Includes time-lapse.
  • Published: 1998
  • Publisher: IWF (Göttingen)
  • Language: English
09:55 IWF (Göttingen) German 1998

Abschuß von Ballistosporen bei Basidiomyceten

Alle Ständerpilze, die ihre Sporen abschießen, folgen demselben Mechanismus: Morphologische und physiologische Eigenschaften der Sporenwand bewirken, daß zwei Flüssigkeitstropfen entstehen. Die schlagartige Veränderung der Oberflächen- und Grenzflächenenergie beim Zusammenfluß beider Tropfen wird als Impuls für den Abschuß genutzt. Itersonilia perplexans, ein leicht zu handhabender aquatischer Pilz, dient als Untersuchungsobjekt. Der Film stellt diesen Pilz vor, zeigt erstmals die Vorgänge, die dem Abschuß vorausgehen, und dokumentiert Experimente, welche die Herkunft der Tropfen klären. Ein Trick verdeutlicht die Vorgänge und physikalischen Verhältnisse beim Abschuß. Mit Zeitraffung.
  • Published: 1998
  • Publisher: IWF (Göttingen)
  • Language: German
04:37 IWF (Göttingen) German 1976

Mitteleuropa, Oberpfalz - Luzia-Gehen in Sattelbogen

In the area of Cham (Upper Palatinate) a bogy appears at the eve of Dec. 13th, the day of Saint Lucia, which is called "Luzia" or "Luzl". About the year 1930 this custom was still practised in the whole of north-east Bavaria especially by the farm workers. "Luzia" threatens to rip up the children's stomachs with her sickle and to fill them with bricks. Today this figure is widely rejected because of its negative effects on the children's minds.
  • Published: 1976
  • Publisher: IWF (Göttingen)
  • Language: German
16:25 IWF (Göttingen) German 1995

Salzbildung in Meerwassersalinen

Seit dem 13. Jahrhundert wird in den Salinen von Secovlje (Portoroz) in Slowenien Salz gewonnen. Hier kann beispielhaft die Salzbildung bei der Eindunstung von Meerwasser studiert werden. Die geochemischen und mikrobiologischen Bedingungen in den Eindunstungsbecken sind vergleichbar mit Salzbildungen in der geologischen Vergangenheit. Die Konzentration des Meerwassers mit der Bildung von Carbonaten, Gips und Steinsalz wird dokumentiert und mit Graphiken und Mikroaufnahmen erläutert. Siehe auch Filme B 1839 und C 1906.
  • Published: 1995
  • Publisher: IWF (Göttingen)
  • Language: German
03:58 IWF (Göttingen) German 1983

Die Briggs-Rauscher-Reaktion als Modell einer chemischen Uhr

Chemische Oszillationsreaktionen werden am periodischen Auftreten und Verschwinden eines Jod-Stärke-Komplexes sichtbar gemacht. Das Oszillieren beruht auf autokatalytischen Reaktionen, bei denen in rhythmischer Folge Zwischenverbindungen oxydiert und reduziert werden. Die Gesamtreaktion wird durch die Dekarboxylierung von Malonsäure getrieben. Mit Zeitraffung.
  • Published: 1983
  • Publisher: IWF (Göttingen)
  • Language: German
Offline Collection IWF (Göttingen) Silent film 1975

Salvia pratensis (Labiatae) - Pollination durch Bombus spp. (Hymenoptera); Melittophilie

The protandrous gullet flowers of the Meadow Clary (Salvia pratensis), typical (bumble-)bee-flowers, are explored for nectar and pollinated by workers of Bombus ssp. By forcing their way in, the visitors set the ingenious lever mechanism of the stamens in motion which dusts their back with pollen. At a later stage the mature stigma is exposed in a corresponding position. Illegitimous visitors (small Apidae, Hover-Flies) fail to effect pollination being incapable to reach the nectar or by-passing the lever-arms.
  • Published: 1975
  • Publisher: IWF (Göttingen)
  • Language: Silent film
Offline Collection IWF (Göttingen) Silent film 1975

Campanula rotundifolia (Campanulaceae) - Pollination durch Apis mellifica (Hymenoptera); Melittophilie

Structure and pollination of a bell-shaped bee-flower are shown by the example of the Harebell, Campanula rotundifolia. The visitors - honey-bees - suck nectar from the protected epigynous chamber on the flower bottom. Hereby they touch ventrally the style which is immature at the first stage of the protandrous flower, serving as a pollen discharger; during the female stage the stigma is exposed in the same position. The process of development of both phases is presented by quick-motion pictures.
  • Published: 1975
  • Publisher: IWF (Göttingen)
  • Language: Silent film
Offline Collection IWF (Göttingen) Silent film 1975

Melandrium rubrum (Caryophyllaceae) - Pollination durch Gonepteryx rhamni (Lepidoptera); Psychophilie

The film demonstrates the pollination of the Red Campoin (Melandrium rubrum, Silene dioica), a dioecious butterfly-flower, by the Brimstone (Gonepteryx rhamni). The structure of the staminate and pistillate flower, details of nectar exploration and pollen transfer in both sexes are shown in close-up pictures.
  • Published: 1975
  • Publisher: IWF (Göttingen)
  • Language: Silent film
26:03 IWF (Göttingen) Original sound, no spoken text 1965

Gildefest in Krempe

The target practice of the riflemen's association founded in 1541 is celebrated every year with broad public resonance. The order of events is: silver polishing, presentation of sabres, wreath making and invitation to the festival, flag throwing, target shooting, and proclamation of the new king, king's dinner.
  • Published: 1965
  • Publisher: IWF (Göttingen)
  • Language: Original sound, no spoken text
08:37 IWF (Göttingen) German 1983

Die Zhabotinsky-Reaktion als Modell einer Musterbildung

Dissipative Muster bilden sich in ursprünglich einfachen chemischen Verbindungen. Ausgehend von Schrittmacherzentren pflanzen sich chemische Wellen einer Redoxreaktion fort, die am Farbumschlag eines Redoxkatalysators erkennbar ist. Die Dekarboxylierung der Malonsäure treibt die Gesamtreaktion. Die Musterbildung bei der Aggregation der Amöben von Dictyostelium (Aufnahmen in Zusammenarbeit mit G. Gerisch, 1963) verläuft analog.
  • Published: 1983
  • Publisher: IWF (Göttingen)
  • Language: German
Offline Collection IWF (Göttingen) Silent film 1975

Anthriscus silvestris (Umbelliferae) - Pollination durch verschiedene Dipteren und Hymenopteren; Allotropie

Insect activity on the umbels of Anthriscus silvestris (Cow Parsley, Umbelliferae, Apiaceae) is shown as an example of pollination of allotropous (allophilic) blossoms with open nectar, by a series of low-specialized visitors. Structure and floral stages of the single flower as well as the behaviour of insects, especially hover-flies feeding nectar and pollen, are demonstrated in detail.
  • Published: 1975
  • Publisher: IWF (Göttingen)
  • Language: Silent film
21:39 IWF (Göttingen) Original sound, no spoken text 1978

Südwest-Europa, Portugal - Dreschen und Dreschbrauch in Tecla

The sheaves spread out are treshed with flails. The threshers are working in teams of five persons arranged in two lines close to each other. The discovery of a stuffed sheepskin is the beginning of a ceremonial threshing custom. After nightfall the sheepskin is burnt in the open air.
  • Published: 1978
  • Publisher: IWF (Göttingen)
  • Language: Original sound, no spoken text
07:44 IWF (Göttingen) Original sound, no spoken text 1978

Südwest-Europa, Portugal - Stockspiel in Basto

The film shows a contest played with stout poles. Various forms are presented: single combat (between two opponents), one against two, one against three, and finally one against a group of adversaries.
  • Published: 1978
  • Publisher: IWF (Göttingen)
  • Language: Original sound, no spoken text
03:05 IWF (Göttingen) Original sound, no spoken text 1977

Hyla arborea (Hylidae) - Quaken (Freilandaufnahmen)

6 short spots of several European tree frogs (Hyla arborea, Hylidae) from Southern Germany, producing their mating calls by night.
  • Published: 1977
  • Publisher: IWF (Göttingen)
  • Language: Original sound, no spoken text
11:16 IWF (Göttingen) German 1999

Lebenszyklus des roten Brotschimmels Neurospora crassa

Der Ascomyzet Neurospora crassa, der für genetische Untersuchungen vielfach eingesetzt wird, bringt an seinem haploiden Myzel drei reproduktive Strukturen hervor: Makrokonidien, die der vegetativen Verbreitung dienen, Mikrokonidien, die zudem sexuelle Funktion übernehmen, und Protoperithezien, die nur sexuelle Funktion haben. Der Film dokumentiert, z. T. in Zeitraffung, die wichtigsten Phasen des Lebenszyklus: Myzelwachstum, Makrokonidien- und Ascosporenkeimung, Entstehung von Perithezien, verschiedene Entwicklungsphasen von Haken und Asci. Das Ergebnis von Kreuzungsversuchen zwischen schwarzporigem Wildtyp und farbloser Mutante ist einbezogen.
  • Published: 1999
  • Publisher: IWF (Göttingen)
  • Language: German
24:48 IWF (Göttingen) English 1995

Life Cycle of the Rust Fungus Puccinia graminis

Rust fungi are phylogenetically very old pathogens attacking cereals and other plants. The life cycle of Puccinia graminis involves five different spore types on two alternate hosts, barberry and cereals or grasses. It is therefore suitable as an exemple of rusts in teaching. In collaboration with John Webster, its life cycle has been documented for the first time. With the help of time lapse and cinemicrography processes such as germination, formation and discharge of spores were observed. The complicated nuclear behaviour is also shown. Graphs are used to structure, explain and summarize the topic. This video can be used to teach students at university or schools, but is also appropriate for private study.
  • Published: 1995
  • Publisher: IWF (Göttingen)
  • Language: English
24:33 IWF (Göttingen) German 1995

Lebenszyklus des Rostpilzes Puccinia graminis

Der Schwarzrost ist ein in Europa ernst zu nehmender Schadorganismus des Getreides. Der Film dokumentiert den vollständigen Lebenszyklus auf den beiden Wirtspflanzen Berberitze und Getreide. Er zeigt ausführlich Entwicklung und Funktion der 5 Sporentypen mit Hilfe von zeitgleichen Feld- und Laboraufnahmen, Zeitraffung, Mikrokinematographie und Zeichentrick. Das Kerngeschehen, wie Dikaryotisierung, Karyogamie und Meiose, wird ebenfalls durch Zeichentrick dargestellt.
  • Published: 1995
  • Publisher: IWF (Göttingen)
  • Language: German
13:31 IWF (Göttingen) English 1997

Biology of the Mosquito Anopheles

The mosquito is widely distributed over the whole world and is important as carrier of malaria. The development cycle is demonstrated using Anopheles stephensi: egg laying, morphology, behaviour and pupation of the larvae. Typical characteristics of males and females are shown, as well as the sucking of blood, which is needed for egg development.
  • Published: 1997
  • Publisher: IWF (Göttingen)
  • Language: English
13:28 IWF (Göttingen) German 1997

Biologie der Stechmücke Anopheles

Die Stechmücke Anopheles ist weltweit verbreitet. Sie spielt eine wichtige Rolle als Überträger der Malaria. Am Beispiel von Anopheles stephensi wird ihr vollständiger Entwicklungszyklus gezeigt: Eiablage, Entwicklung der Eilarve und das Schlüpfen, Verhaltensweise und Morphologie der Larven, Morphologie der Puppen und der Schlüpfvorgang der adulten Mücken. Die wesentlichen Merkmale der männlichen und weiblichen Mücke werden vorgestellt sowie das Blutsaugen, das Voraussetzung für die Eireifung ist. Mit Zeitraffung.
  • Published: 1997
  • Publisher: IWF (Göttingen)
  • Language: German
Offline Collection IWF (Göttingen) German 1981

Inter- und intraspezifische Nahrungskonkurrenz bei Altweltgeiern

Vultures often gather in large numbers on carcasses. This leads inevitably to inter- and intraspecific competition for food. The different preferences of the individual species for certain parts of carcasses alleviates this to some extent. With the exception of the Bearded Vulture (Gypaetus barbatus) and the Palm-Nut Vulture (Gypohierax angolensis), the old world vultures can be divided into three feeding types: 1) pulling; 2) tearing; 3) pecking species. Species of the genus Gyps belong to type 1; with the exception of the Hooded (Necrosyrtes monachus) and the Egyptian vulture (Neophron percnopterus) which both are type 3 feeders, all other species belong to type 2.
  • Published: 1981
  • Publisher: IWF (Göttingen)
  • Language: German
Offline Collection IWF (Göttingen) German 1994

Motilität - Cilien- und Flagellenbewegung

Flagella or cilia are present in eucaryotes from protists up to mammals. They serve the purpose of locomotion and transport of materials. The basic structure of the axonemes of flagella and cilia is identical and is visualized by means of electronmicrographs and animated graphics. Complex coordination of the cilial beat is explained with reference to Paramecium and reconstructed in animated sequences. Film shots from the years 1963 to 1991.
  • Published: 1994
  • Publisher: IWF (Göttingen)
  • Language: German
12:18 IWF (Göttingen) English 1995

Controlling the hardness of workpieces during immersion cooling

The quenching of heated components in water, oil and polymer solutions is examined. The wetting process is defined by the type of quenchant used. The cooling behaviour is shown in real time and in slow-motion and elucidated by diagrams. The spatial temperature distribution is visualized by simulations and animation. The measurement of hardness, techniques of crack detection as well as various methods used by hardening companies are presented.
  • Published: 1995
  • Publisher: IWF (Göttingen)
  • Language: English
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